Improvement in elevators



R. B. DAWSON."

Elevator.

No. 221,037. Patented Oct-.28, |5879.

W/TNESSES.

Aim,

N.PETERS, PHOTO-LITHCGRAPHER. WASHINGTON. D. C.

UNrTED STATES- PATENT (3F-Flon.

RODMAN B. DAWSON, OF BROOKLYN, NEY YORK.

IM PROVEM ENT` IN lELEVATO RS.

Specification forming part of Letters Patent No. 221,037, dated October 2S, `1879 g application tiled September l5, 189.

To all whom it may concern:

Be it known that I, RomrAN- B. Dawson, a citizen ofthe United States, residingin Brooklyn, in the county of Kings and State of New y York, have invented certain new and useful Improvements in Elevators or Lifts, of which the following' is a specification.

My invention relates to a means of raising andlowerin gthe cars or platforms of elevators, lifts, or hoists; and it consists, mainly and es sentially, of two or more screw-sections arranged telescoprically, the upper extremity -ot' the upper screw-section being secured to the car or platform so that it may not rotate, and thc lower section, which is not externally threaded, bein arranged vertically in bea-rings, so that it may he rotated and the sec tions above projected successi-vely, one by the other, bythe. said rotation of the lower sec tion.

It also consists in several minor features of construction, all as will be more particularly hereinafter set forth.

In the drawings, which serve to illustrate my invention, Figure l is an elevation, partly in section, showing the elevator complete. Fig. 2 is a horizontal section taken in tbe plane ofthe line a :t in Fig. 1. Fig. 3 is an enlarged sectional detail view taken through the point where one section enters another. p

Arepresents any suitable frame-work, wherein the caror platform B of an elevator is guided in its ascent and descent. Oisatubularshaft, stepped at a on a .pintle in its lower end, and provided with a bearing at b, near its upper extremity. DD D are screw-sections. The first two are tubular, and the lastnamed may or may not be tubular, as preferred.

At the upper extremities of the sections D D and the shaft-section O are lixed'or formed nut-s c c, which are threaded internally to tit the threads of the screws, which enter them as shown. The internal construction is best illustrated in Fig. 3.

The upper section, D, is preferably provided with some form of lian ged cap, d, whereby it is rigidly securedto the car B.

The car or platform is guided and prevented from turning by grooved friction-wheels e e,

arranged to take over thc angles of the guideframe posts.

SomeV other well-known means of guiding and steadying the car may be substituted for that shown, however, without departing from my invention.

So far as described the operation is as follows: The. lower section or shaft, C, being rotated in the proper direction, the sections D D D are projected to their full length, thus elevating the car B. By reversing the motion and rotating the shaft or lower section in the opposite direction, the three upper sections are retracted and telescopcd, thus lowering the car again.

The screw-sections are projected iu succession, the upper one, D, being, ordinarily, projected first, then the section D', and then D, and so on down if more are employed. When the iirst-named section is run up to its full length a stop on its lower extremity prevents its further extension, and stops the revolution of the next section, D, below, when it too begins to protrude. This section, when projected, performs the same service for the next below, D, and so on until all are projected. Thus it will be seen that all of t-he sections are mutually dependent in theirmovements, and this enables me to project all of them directly from the rotation ofthe shaft (l. While one screw-section is being projected endwise the others continue to rotate with thc sectiony C, and as soon as this rotation is checked they begin to move longitudinally.

To steady the sections in their movement I provide spiders or cross-head guides E E, arranged to clasp the sections at their upper ends, preferably taking into grooves in the nuts c c, which form, in a manner, journal-bearings for the sections to rotate in.V The arms of these spiders are provided, by preference, with friction wheels or sheaves to bear against tracks on the frame-work in their ascent, similar to those on the car B.

To assist in steadying the sections in their movement and to prevent them from being run out of the nuts 4when projected, I provide their lower extremities with stop-Hangers or pistons g, as indicated in FiO. 3. These fit neatly into the bores of the sections they play in, and serve the double purpose above stated.

F F are unter-gears, one mounted on the section or shaft C, andthe other on a suitable shaft, h., provided with a crank, Gr.

The appliances for rotating the lower scction or shaft, C, are common and well known, and I only employ them to illustrate the operation of the hoist. In most cases steamen giues provided with a throttle-valve and reversingear arranged to be operated from the platform will doubtless be employed; but these form no part of my present invention.

To prevent an accumulation inside the sections of oil from the screws, the stops g should be bored or tubular and should be tinted or bored, as indicated by the dotted line in Fig. 3, so that the oil may escape.

The foot of the section C may be stepped in a recess, 1', at the base, and the oil from the sections be allowed to drip into this, thus insuring perfect lubrication at that point.

To avoid noise as much as possible I prefer to provide the gears F F with wooden cogs, and in some cases friction-gears may be cmployed to good advantage. Y

Having described what I believe to be the preferable method of constructing my inven tion, I wish it understood that I do not conine myself to that shown, as various colorablc alterations, which would not materially affect theinvention,willreadilysuggestthemselvesas, for instance, the tubular sections might be internally, as well as externally, screw-tlneaded their whole length, and the pistonsg might be replaced by any form of stop or check; or the lower shaft or section, C, may be shortened and rotated only in bearings at the upper end, the section D heilig' allowed to protrude through it when down. Indeed, this lower section may be lnade of any shape or forni best suited to the circumstances.

I contemplate making the upper or screwthreaded sections of steel, and the nuts c c of hard brass or any suitable metal. Single, double, or many threaded screws may be employed.

Having thus described my invention, I wish it understood that I do not claim the device shown in the patent of Thomas and Joerns, No. 168,485, dated March 2, 1875, and consider it to be entirely different from my herein-described invention in many important respects; but

IVhat I do claim is l. In an elevator or hoist, the arrangement between the section or nut C and the screwsection D, which is secured to the non-rotative car or platform, of the telescopic tubular screw-sections D D, provided with fixed nuts c c, internally screw-threaded, whereby the rotation ot' the said nut or section C is caused to protrude the said sections successively and elevate the platform, substantially as set forth.

2. In an elevator or hoist, the combination ot` a rotary section or nut, C, the screw-sections D D D, arranged telescopically, as shown, the upper section being secured rigidly to the car, and the others provided with Iixed internally-threaded nuts c c, and all arranged tolbe protruded successively by the rotation of the nut C and the non-rotative car B, all arranged to operate substantially as set forth.

3. The serew-sectious D D D, provided with pistons g, or other similar stops, to prevent them from being projected or driven out of the nuts c c when protruded, and to form guides to steady them in their movements, substantially as shown and specilied.

4. In a telescopic screw for hoists, the intermediate sections, D D,provided with fixed internally screw-threaded nuts c c and stops on their lower ends, substantially as and for the purposes set forth.

5. lhe tubular screw-sections D D, provided with fixed nuts c c, grooved to receive spiders or guides E, in combination with said guides, the sections C D, and the car B, all arranged substantially as set forth.

6. The lower rotative tubular section, C, provided with a nut, c, and a bearing', b, at its upper end, and a pintle, a, at its lower end, substantially as and for the purposes set forth.

7. The combination ot' a car, B, arranged to move in a guide-frame, A, and a telescopic screw, consisting of the moving sections D D D7 provided with pistons g, and the rotative nut or section C, arranged centrally beneath it, the upper section being fixed to the car, and the other sections being provided with fixed nuts c c and guides E E, all substantially as set forth. i

In witness whereof I have hereunto signed 'my name in the presence of two subscribing witnesses.

RODMAN B. DAWSON.

Witnesses:

HENRY CONNETT, ARTHUR G. FRAsER. 

